Does omega-3 PUFAs supplementation improve metabolic syndrome and related cardiovascular diseases? A systematic review and meta-analysis of randomized controlled trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 37222574 · doi:10.1080/10408398.2023.2212817
What was done
This systematic review and random-effects meta-analysis evaluated 48 randomized controlled trials with a total of 8,489 participants to determine the effects of omega-3 polyunsaturated fatty acid (PUFA) supplementation on lipid profiles, blood pressure, and inflammatory markers in patients with metabolic syndrome (MetS) and related cardiovascular diseases (CVDs). Searches were conducted in PubMed, Embase, and Cochrane Library through November 1, 2022.
What was found
Omega-3 supplementation significantly reduced: - Triglycerides (WMD: -18.18 mg/dl; 95% CI: -25.41, -10.95; p < 0.001) - Total cholesterol (WMD: -3.38 mg/dl; 95% CI: -5.97, -0.79; p = 0.01) - Systolic blood pressure (WMD: -3.52 mmHg; 95% CI: -5.69, -1.35; p = 0.001) - Diastolic blood pressure (WMD: -1.70 mmHg; 95% CI: -2.88, -0.51; p = 0.005) - IL-6 (WMD: -0.64 pg/ml; 95% CI: -1.04, -0.25; p = 0.001) - TNF-α (WMD: -0.58 pg/ml; 95% CI: -0.96, -0.19; p = 0.004) - CRP (WMD: -0.32 mg/l; 95% CI: -0.50, -0.14; p < 0.001) - IL-1 (WMD: -242.95 pg/ml; 95% CI: -299.40, -186.50; p < 0.001) It significantly increased HDL (WMD: 0.99 mg/dl; 95% CI: 0.18, 1.80; p = 0.02). No effects were observed on LDL, MCP-1, ICAM-1, or sE-selectin. Doses ≤ 2 g/day showed greater overall benefit, and intervention duration correlated linearly with reductions in TG, IL-6, TNF-α, and CRP.
Why it matters
This review synthesizes conflicting trial data, demonstrating consistent surrogate marker improvements across lipid, vascular, and inflammatory pathways in patients with cardiometabolic disease, particularly at doses of 2 g/day or less.
Limits
The abstract reports only surrogate biochemical and physiological markers rather than hard clinical endpoints like cardiovascular events or mortality. Formulations (EPA vs. DHA ratios), background statin use, and baseline dietary omega-3 intake were not detailed in the abstract.
Cited by
- supports Scientific evidence demonstrates that omega-3 supplementation exerts anti-inflammatory effects.